A two component galvanic anode cathodic protection (CP) system was designed, procured and installed on an offshore loading pipeline. An estimate of the initial coating damage (presumed undetected and buried) was factored into the coating efficiency data for design. The contingency factor for current spread of 1.5 times the bracelet spacing was verified during detailed design and confirmed during construction. After the completion of the onshore pipeline it was revealed that the contractor had buried three aluminum bracelets at the landfall section near the
shoreline, contrary to the construction drawings. Various options and their cost impact to remedy the situation were reviewed. Concerns regarding passivation of buried aluminum and excessive current drain from the onshore magnesium systems were dismissed. This was based on the geotechnical data and limited area of influence of the two dissimilar anode metals at the landfall. An initial potential survey of the onshore portion prior to it's activation indicated that current propagation provided by the offshore system (and the onshore bracelets) extended all the way to Kilometer Post 0.00 near the isolating flange at the terminal.